Marking apparatus

ABSTRACT

A marking apparatus for a material to be marked with an electrophotosensitive layer comprises means for feeding the material, a developing roller having a resilient, nonconductive surface layer, said roller being so mounted as to contact only with the material, and a suction means for sucking an excessive developer after developing with a time interval necessary for acccomplishing developing operation.

United States Patent 11 1 Matsumoto et a1.

[ MARKING APPARATUS [75] inventors: Seiii Matsumoto; Satoru Honjo;

Kazuhiro Kawaziri; Sigeru Tezuka; Etuo Shiozawa, all of Asaka. Japan[73] Assignee: Fuji Photo Film Co.. Ltd.. Minamiashigara, Japan 122]Filed: Mar. 30, 1973 [211 Appl. No.: 346,292

[30] Foreign Application Priority Data Apr. 3. 1972 Japan 47-33371 [52]U.S. Cl. 118/637; 118/70; 118/104;

ll8/D1G. 23 [51] Int. Cl. (303G 13/10 [58] Field of Search 118/70, 104,DIG. 23,, 637

156] References Cited UNITED STATES PATENTS 3.363.530 1/1968 Rice118/637 X 1 51 Sept. 30, 1975 3.369.523 2/1968 Naumann 118/637 3.410.71311/1968 Schneidercit... ll8/D1G. 23

3.461.843 8/1969 Noon ll8/D1G. 23 3.552.353 1/1971 Labombarde 118/703.701.337 10/1972 Borelli et a1. 118/637 3.741.157 6/1973 Krause 118/6373.741.643 6/1973 Smith ct al.. 355/10 3.830.199 8/1974 Saito et a1 118/637 Primarv E.\'aminerMervin Stein Attorney. Agent, or Firm-Gerald J.Ferguson, Jr.; Joseph J. Baker [57] ABSTRACT A marking apparatus for amaterial to be marked with an electrophotosensitive layer comprisesmeans for feeding the material, a developing roller having a resilient.nonconductive surface layer, said roller being so mounted as to contactonly with the material, and a suction means for sucking an excessivedeveloper after developing with a time interval necessary foracccomplishing developing operation.

12 Claims, 10 Drawing Figures Patent Sept. 30,1975 Sheet 1 of3 3,908,594

FIG. IA

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FIG. 3

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L ZilllllllllifllllllIK- MARKING APPARATUS BACKGROUND OF THEINVENTION 1. Field of the Invention This invention relates to a linemarking apparatus on a sheet material such as steel plate.

It is troublesome to form mark lines on a surface of steel plate or thelike and an automatic marking by utilizing an electrophotographictechnique has highly been desired. It is, however very difficult toapply a developer only in the necessary range of a surface of materialto be marked during feeding the material by conveyor.

An object of the invention is to provide an apparatus for forming markedlines on a surface of material to be marked by coating anelectrophotographic light sensitive layer thereon and forming aninformation such as marked lines with an electrophotographic process.

Other features and advantages of the invention will be made apparentfrom the following description of preferred embodiments thereof taken inconjunction with the accompanying drawings.

2. Brief Description of the Drawings FIG. 1 is a schematic sideelevation of one embodiment of the invention where FIG. 1A illustrates acharging step, FIG. 18 illustrates an image exposure step, and FIG. 1Cillustrates a developing and cleaning step in accordance with theinvention and FIGS. 2 to 8 are schematic side elevations of theessential parts of embodiments in accordance with the inventionrespectively.

DETAILED DESCRIPTION OF THE EMBODIMENTS FIG. 1A, 1B and 1C representdevices performing the inventive processes in which FIG. 1A is acharging process, FIG. 18 an exposure process and FIG. 1C a developingprocess. In FIG. 1A, numeral 3 represents a material to be marked madeof, for example, a steel plate and a light sensitive layer 2 (the layeris made of photoconductive powder material such as zinc oxide ortitanium oxide mixed with a resin having high insulating property suchas silicon acrylic resin or alkyd resin and is applied on the surfaceabout from 5 to 30a in thickness). Numeral 4 is a corona dischargeelectrode of which size is about from 30 to 100 in diameter. The .platelike material 3 to be marked is fed with a conveyor 7 in the directionshown by an arrow and the material is charged with the electrode 4during passing under the electrode.

As shown in FIG. 1B, an original 5 having an original draft, such asmarking lines thereon is superposed on the light sensitive layer 2,exposing them to a suitable light source 6, thus forming anelectrostatic latent image in the light sensitive layer 2.

The material to be marked having the latent image is fed to thedeveloping station shown in FIG. 1C. As seen in FIG. 1C, a developingroller 8 having a resilient, porous and electrically insulating surfacein-which liquid developer being infiltrated is driven on the surfacehaving the latent image under a suitable pressure to develop the image.The roller 8 is so constructed that has a core made of metal, vinylchloride or acrylic resin and a urethane foam band 0.5 to 10 cm inthickness wound thereon. As a liquid developer, Kerosene, lsopar E, H orG (isoparafil solvent) or cyclohexane or the like in which carbon black,phthalocyanine blue, as a pigment,

being dispersed with suitable charge adjusting agent. After passingthrough the roller 8, the excessive developer is absorbed with a suctionroller 9, drying with air ejected from a nozzle 10.

In FIG. 2, an embodiment of an apparatus for applying developer onto thelight sensitive layer 2 is shown. The roller 8 is, as set forth above,formed with a core made of metal or vinyl chloride or acrylic resin anda surface layer made of polyurethane foam, polyethylene foam or rubberfoam which is resilient, porous and having a high insulating property.The material 3 to be marked fed with the conveyor 7 passes through underthe roller 8 to receive the developer by squeezing thereof due tocompression of the roller onto the material surface. According to beadvance of the material and the rotation of the roller 8, the excessdeveloper supplied on the material surface can be absorbed into theroller again upon leaving from the material surface, so that a suitableamount of developer may be applied on the surface.

It is preferable that the thickness of the material to be marked is morethan a radially compressed distance of the resilient portion of theroller for assuring proper supply of liquid developer. According to ourexperi ments, a material to be marked having a thickness of more than 3mm makes it. possible to proper developer supply only in the necessaryarea for marking without any excess supply into the unnecessary area.When a thickness of material to be marked is less than 3 mm, a platemember having about the same size with the material is positioned on theconveyor and the material is superposed on the plate member to make thetotal thickness of them more than 3 mm.

As set forth above, by making a hight of a material to be markedsubstantially more than 3 mm a proper amount of developer can be appliedto only a necessary area with compressed drive of the porous developingroller having liquid developer therein.

In FIG. 2, numeral 21 represents an arm on which the roller 8 beingrotatably mounted at its one end and the arm is also swingably mountedby means of a pin 22 at its other end. When lacking in developer, theroller may be rotated to a position shown by numeral 8'. Numeral 23 is anozzle for supplying developer to the roller and during supplyingdeveloper the roller rotates in the direction shown by an arrow. Numeral24 is a squeezing roller for removing'an excessive developer. Theexcessive developer will be collected in a reservoir R through a tray25. The developer withdrown into the reservoir R will be fed to thenozzle 23 by means of a pump P.

After developer supplying operation has finished the roller 8 will bereturned to its operating position from said developer supply position.During the roller is in the supply position, the conveyor 7 is stopped.

FIG. 3 shows a schematic elevational view of another embodiment inaccordance with the invention in which a plate like material to bemarked is fed in constant speed in the direction shown by an arrow. Alight sensitive layer 2 has a latent image therein formed during passingthrough a charge and an exposure process. A developing roller 8 having aresilient, porous surface layer rotates around a shaft thereof. Duringpassing the material 3 under the roller 8 having a developer thereinwith a suitable compression of the resilient surface layer of theroller, the developer in the roller 8 is applied onto the lightsensitive layer 2 of the material.

Upon leaving from the roller surface an excessive amount of thedeveloper on the material will be absorbed to the roller layer again, sothat a proper amount of the developer can always be applied onto thelight sensitive layer 2.

Since the surface of the roller 8 has sufficient resiliency, itcompletely compensates for a slight roughness due to a roughness of thematerial surface and minimizes irregularity of developer supply. If thematerial to be marked has a thickness of more than 3 mm, the outerporous surface layer of the roller is not compressed when it nevercontacts with any other ones than the material and thus uselesscomsumption of developer does not occur.

Numeral 31 represents a developer supply nozzle, numeral 32 is asqueezing roller for retaining a proper amount of developer in theroller layer.

An excess developer, over flown and squeezed from the roller will becollected in a reservoir R through a tray 33. Numeral 34 is a doctorblade for preventing an excess developer from adhering to the rolleragain. The squeezing roller may be driven with a motor (not shown) orthe roller 8.

An amount of developer about from 0.1 to 0.8 c.c./cm in the roller layeris preferable, a less developer causes insuficient development and anexcessive one stains the surface of the marked surface.

A preferable amount of a developer to be supplied from the roller isdetermined in accordance with an amount of toner included in thedeveloper and when an amount of the developer having toner X g/l in therange of to 500 c.c./m a preferable amount of the developer to besupplied onto the photosensitive surface can be indicated by thefollowing expression:

l X IOOOX (40 X )cc/m For example, a preferable amount of developer,when including 4 g/l toner weight, is about from to 250 c.c./m developerof about from to 500 c.c./m when including 2 g/l of toner, developerabout from 40 to 500 c.c./m when including 1 g/l of toner, developerabout from 5 to 125 c.c./m when including 8 g/l of toner and developerabout from 5 to 100 c.c./m when including 16 g/l toner.

A blurred image may be obtained with too less developer and an excessdeveloper stains a light sensitive surface and is wasteful.

As the porous member of the roller has sufficient resiliency, itcompensates for a slight unevenness of a light sensitive surface of amaterial due, for example, to a roughness of the surface of thematerial, for inaccuracy of a conveyor and the like. According to ourexperiments, porous member having bubles of which di ameters are in therange of from 50 to 900a could retain the optimum amount of developerand a roller of which diameter was of about from to 400 mm was the mostproper for use.

A developer contained in a roller tends to drop out therefrom due to theexistence of gravity when stopping the roller, and if not drop out thedeveloper is apt to collect in the under space of the roller. Thus, itis de sirable to rotate the roller continuously not only duringsupplying the developer to the material but also during idling. It ispreferable to rotate the roller more than 10 rpm. during there is nocontact of the roller with a material.

FIG. 4 represents an embodiment of a suction roller which sucks adeveloper already used after the developer has been applied to amaterial to be marked. After a developer has been applied to aphotosensitive layer on a material to be marked and a latent image hasbeen developed, the material is fed to a position where a suction rolleris mounted about 5 to 200 cm from the developing roller. Used developeris removed from the material by the suction roller.

The suction roller 9 has a core made of metal, plastic or others and aresilient, porous and a high oil absorbing layer made of, for example,polyethylene foam layer mounted around the core. Bubbles contained inthe suction roller having substantially similar to or slightly less thanthat of the developing roller in sizes, namely about 30 to 700g indiameter can preferably be used. Such suction roller will remove useddeveloper promptly and sufficiently. The diameter of the suction rollerof about 2.5 to 40 cm is optimum. Numeral 41 is a suction nozzle whichremoves the developer already sucked developer to the roller. The sipslit of the nozzle about 2 to 20 mm in width and a pressure of from 400to 1000 mm water head in a suction pump P are preferable.

Thus, even if there is a sight roughness on a surface of a material tobe marked, most of used developer can be removed by means of suctioneffects of a suction roller and a suction pump for preventing thedeveloper from collecting in the suction roller.

It is preferable to determine a position at which the suction roller isto be positioned so that the suction roller contacts with used developeron the material to be marked about 0.5 to 20 seconds later afterdeveloping operation has finished. Therefore, the position is about 5 to200 cm far from the developing position when the conveyor velocity is 10cm/sec.

FIG. 5 represents another embodiment of a suction roller device. Useddeveloper can be absorbed into a porous layer of a suction roller 9through a nozzle 51 and then sucked with a suction pump P. Numeral 52 isa rotatable roller mounted at the slit of the nozzle 51 for squeezingthe developer in the roller 9. This rotatable roller 52 not only sucksthe developer in the roller 9 effectively but also prevents wear of theporous layer of the roller 9.

FIG. 6 represents further embodiment of a suction roller device. Ahollow tube like casing 62 having 212'. axially formed opening has aninner tube 6i having a plurality of small holes and the exposed portionof the inner tube is forcibly in contact with the porous surface of thesuction roller 9 for sucking used developer through the opening as shownin the figure. The central hollow portion inside the tube 61 ismaintained a negative pressure with a suction pump (not shown), so thatused developer can be sucked into the hollow portion. The numeral 62 isthe casing for preventing entrainment of air from the holes which arenot in contact with the suction roller 9. Numeral 63 is a trough forcollecting sucked developer.

FIG. 7 represents a device for use in a drying process. Numeral 71 is anair nozzle positioned above the light sensitive surface being fed by aconveyor 7 about 2 to 30 mm and effects squeezing and drying theremained developer. An excessively high air velocity tends to damage animage formed on the material to be marked and a too less velocity causesless effect. A velocity of the air flow in the range of from 0.5 tom/sec and a direction of the air flow in the angular range of from 45 to90 to the surface of the material to be marked is preferable.

FIG. 8 represents another embodiment of a drying process. A suctionroller 9 is in the proximity of an air nozzle 81 for increasing suctioneffect of the roller. The suction roller has a porous and resilientsurface layer and the surface is in contact with a light sensitive layer2. Accompanying with the rotation of the roller 9, sucked developer intothe roller is then sucked into a nozzle 41 and residual returns to theroller 9 due to an air flow from the nozzle 81 and sucked into theroller 9. It is of course that the air flow ejected from the nozzle 81enaporate a part of residual.

The distance between the line that the contact line of the suctionnozzle 9 with the surface of the material to be marked and the line thatthe air flow ejected from the nozzle 81 runs against the surface of thematerial is preferably about from 3 to 50 mm. The angle between the airfiow ejecting direction and the. material surface direction ispreferably decided in the range of 45 to 90.

As set forth above, according to the invention the marking operation onan electroconductive material being more than 3 mm in thickness caneffectively be carried out.

It is course that two or more developing rollers, suction rollers andair nozzles raise a developing and a drying effects.

According to the invention, a high contrast marked line image can beobtained with minimum developer loss on materials to be marked ofvarious dimensions and further a photosensitive layer is upwardlydirected, so that no troubles in mechanical system, especially inexposure system, are encountered.

Although the invention has been described in its preferred form with acertain degree of particularity, it should be understood that thepresent disclosure has been made only by way of example and variouschanges may be resorted to without departing from the spirit of theinvention and the scope of the invention as hereinafter claimed.

What is claimed is:

1. ln apparatus for marking a metallic plate having a surfaceelectrophotosensitive layer theron by charging said layer, imageexposing to form a latent image, and developing said latent image, theimprovement of a conveyor belt for feeding said metallic plate disposedon one side thereof, a developing roller disposed on the other side ofsaid metallic plate and directly opposite to at least a portion of saidconveyor belt having a porous, sponge like, non-conductive surfacelayer, said roller being so mounted as not to contact said conveyor beltbut to contact said electrophotosensitive layer of the metallic platewith at least the under side of the sponge like surface layer, saidsponge like surface containing a liquid developer for effecting saiddeveloping as it is squeezed against said electrophotosensitive layerand suction means for removing excessive developer from said metallicplate after a time lag necessary to complete the developing operation.

2. The improvement in claim 1 where said image to be developed is a lineimage.

3. The improvement of claim 1 where said developing roller has adiameter of 2.54() cm, and includes a solid core covered with saidsponge like layer having a thickness of 0.5-10 cm.

4. The improvement as in claim 1 where the bubbles contained in saidsponge like layer have a diameter in the range of 50 to 900 1..

5. The improvement as in claim 1 including means for supplying developerdirectly onto the surface of the sponge like layer.

6. The improvement as in claim 1 where the suction means comprises asuction roller having a core and a resilient, porous layer mountedthereon, which is pressed against the material to be marked.

7. The improvement as in claim 6 where the outside diameter of saidsuction roller is 25-40 cm.

8. The improvement as in claim 6 where said suction means includes asuction nozzle to absorb the developer contained in the suction rollerlayer, said nozzle being pressed against the surface of the porouslayer.

9. The improvement as in claim 8 including a roller rotatably mountedwithin said suction nozzle for squeezing the developer in said suctionroller layer.

10. The improvement as in claim 1 including means for insuring that saidmaterial to be marked is greater in thickness than the radialcompression of said sponge like layer as the latter squeezes againstsaid electrophotosensitive layer.

11. The improvement as in claim 1 where said material to be marked isgreater in thickness than the radial compression of said sponge likelayer as the latter squeezes against said electrophotosensitive layer.

12. The improvement as in claim 1 where said sponge like layer containsabout 0.1 to 0.8 c.c./cm of said de-

1. In apparatus for marking a metallic plate having a surfaceelectrophotosensitive layer theron by charging said layer, imageexposing to form a latent image, and developing said latent image, theimprovement of a conveyor belt for feeding said metallic plate disposedon one side thereof, a developing roller disposed on the other side ofsaid metallic plate and directly opposite to at least a portion of saidconveyor belt having a porous, sponge like, non-conductive surfacelayer, said roller being so mounted as not to contact said conveyor beltbut to contact said electrophotosensitive layer of the metallic platewith at least the under side of the sponge like surface layer, saidsponge like surface containing a liquid developer for effecting saiddeveloping as it is squeezed against said electrophotosensitive layerand suction means for removing excessive developer from said metallicplate after a time lag necessary to complete the developing operation.2. The improvement in claim 1 where said image to be developed is a lineimage.
 3. The improvement of claim 1 where said developing roller has adiameter of 2.5-40 cm, and includes a solid core covered with saidsponge like layer having a thickness of 0.5-10 cm.
 4. The improvement asin claim 1 where the bubbles contained in said sponge like layer have adiameter in the range of 50 to 900 Mu .
 5. The improvement as in claim 1including means for supplying developer directly onto the surface of thesponge like layer.
 6. The improvement as in claim 1 where the suctionmeans comprises a suction roller having a core and a resilient, porouslayer mounted thereon, which is pressed against the material to bemarked.
 7. The improvement as in claim 6 where the outside diameter ofsaid suction roller is 2.5-40 cm.
 8. The improvement as in claim 6 wheresaid suction means includes a suction nozzle to absorb the developercontained in the suction roller layer, said nozzle being pressed againstthe surface of the porous layer.
 9. The improvement as in claim 8including a roller rotatably mounted within said suction nozzle forsqueezing the developer in said suction roller layer.
 10. Theimprovement as in claim 1 including means for insuring that saidmaterial to be marked is greater in thickness than the radialcompression of said sponge like layer as the latter squeezes againstsaid electrophotosensitive layer.
 11. The improvement as in claim 1where said material to be marked is greater in thickness than the radialcompression of said sponge like layer as The latter squeezes againstsaid electrophotosensitive layer.
 12. The improvement as in claim 1where said sponge like layer contains about 0.1 to 0.8 c.c./cm3 of saiddeveloper.